Effect of Different Dosing Regimens of Tadalafil or Tamsulosin Combined With 5α-Reductase Inhibitors on Urinary and Sexual Outcomes in Benign Prostatic Hyperplasia (DTT-BPH)

"Effect of Different Dosing Regimens of Tadalafil or Tamsulosin Combined With 5α-Reductase Inhibitors on Urinary and Sexual Outcomes in Benign Prostatic Hyperplasia: A Comparative Clinical Trial Study"

Benign prostatic hyperplasia (BPH) is a common condition among aging men that causes lower urinary tract symptoms (LUTS) and may negatively affect sexual function. This randomized single-blind controlled clinical trial compares the efficacy, safety, and sexual outcomes of different dosing regimens of tadalafil or tamsulosin combined with 5-alpha reductase inhibitors (5ARIs) in men with BPH and enlarged prostate volume. A total of 240 participants were randomly assigned to six treatment groups and followed for 12 weeks. Changes in urinary symptoms, erectile function, ejaculatory function, prostate volume, prostate-specific antigen (PSA), urinary flow rate, post-void residual volume, and adverse events were evaluated to determine the optimal combination regimen.

Study Overview

• Status: Completed
• Conditions: Lower Urinary Tract Symptoms; Benign Prostatic Hyperplasia; Erectile Dysfunction
• Intervention / Treatment: Drug: Tamsulosin; Drug: 5-Alpha Reductase Inhibitor; Drug: Tadalafil

Detailed Description

Benign prostatic hyperplasia (BPH) is one of the most common causes of lower urinary tract symptoms (LUTS) in older men and is frequently associated with impaired sexual function. Alpha-blockers and 5-alpha reductase inhibitors (5ARIs) are widely used for medical management; however, both treatment strategies may adversely affect sexual function. Phosphodiesterase type-5 inhibitors, particularly tadalafil, have emerged as an alternative therapeutic option because they improve LUTS while preserving erectile function.

This randomized, single-blind, controlled clinical trial was conducted at the Department of Urology, Faculty of Medicine, Beni-Suef University, Egypt. The study enrolled 240 eligible men aged 50 years or older with moderate-to-severe LUTS secondary to BPH and prostate volume greater than 40 mL. Participants were randomly allocated into six equal treatment groups comparing different dosing regimens of tadalafil or tamsulosin combined with 5-alpha reductase inhibitors.

The primary objective was to compare improvements in lower urinary tract symptoms using the International Prostate Symptom Score (IPSS). Secondary objectives included evaluation of erectile function using the International Index of Erectile Function-Erectile Function domain (IIEF-EF), ejaculatory function using the Male Sexual Health Questionnaire-Ejaculatory Dysfunction (MSHQ-EjD), maximum urinary flow rate (Qmax), prostate volume, prostate-specific antigen (PSA), post-void residual urine volume (PVR), and treatment-related adverse events.

Participants received treatment for 12 weeks and were assessed at baseline and at the end of the study. Safety was evaluated by monitoring adverse events throughout the study. The findings are expected to identify the most effective and well-tolerated combination regimen for improving both urinary and sexual outcomes in men with benign prostatic hyperplasia.

• Study Type: Interventional
• Enrollment (Actual): 240
• Phase: Phase 4

Contacts and Locations

Study Locations

• Egypt
  • Beni Suef Governorate
    • Banī Suwayf, Beni Suef Governorate, Egypt
      • Beni-Suef University Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Male participants aged 50 years or older.
• Newly diagnosed with benign prostatic hyperplasia (BPH).
• Moderate to severe lower urinary tract symptoms (LUTS), defined as International Prostate Symptom Score (IPSS) > 7.
• Prostate volume >40 mL confirmed by transrectal ultrasonography (TRUS).
• Sexually active with a baseline International Index of Erectile Function-Erectile Function (IIEF-EF) score >10.
• Prostate-specific antigen (PSA) <4 ng/mL and no suspicious findings on digital rectal examination (DRE).
• Able and willing to provide written informed consent.

Exclusion Criteria:

• History of prostate cancer.
• Previous prostate surgery.
• Abnormal digital rectal examination suggestive of malignancy.
• Severe erectile dysfunction (IIEF-EF score ≤10).
• Uncontrolled diabetes mellitus.
• Uncontrolled cardiovascular disease.
• Neurological disorders affecting bladder function.
• Renal impairment.
• Hepatic impairment.
• Active urinary tract infection.
• Bladder stones or other significant urological pathology.
• Known hypersensitivity to tamsulosin, tadalafil, or 5-alpha reductase inhibitors.
• Patients actively seeking fertility treatment.
• Current use of medications known to significantly affect sexual function.
• Concurrent use of nitrates or contraindicated antihypertensive medications.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

6

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Tamsulosin daily + 5ARI daily; Participants received tamsulosin 0.4 mg once daily in combination with a 5-alpha reductase inhibitor administered once daily for 12 weeks.	Drug: Tamsulosin; Tamsulosin hydrochloride 0.4 mg administered orally either once daily or every other day according to the randomized treatment allocation for 12 weeks.; Drug: 5-Alpha Reductase Inhibitor; A 5-alpha reductase inhibitor (finasteride 5 mg or dutasteride 0.5 mg according to routine clinical practice) administered either once daily or every other day according to the randomized treatment allocation for 12 weeks.
Experimental: Tamsulosin daily + 5ARI every other day; Participants received tamsulosin 0.4 mg once daily combined with a 5-alpha reductase inhibitor administered every other day for 12 weeks.	Drug: Tamsulosin; Tamsulosin hydrochloride 0.4 mg administered orally either once daily or every other day according to the randomized treatment allocation for 12 weeks.; Drug: 5-Alpha Reductase Inhibitor; A 5-alpha reductase inhibitor (finasteride 5 mg or dutasteride 0.5 mg according to routine clinical practice) administered either once daily or every other day according to the randomized treatment allocation for 12 weeks.
Experimental: Tamsulosin every other day + 5ARI every other day; Participants received tamsulosin 0.4 mg every other day combined with a 5-alpha reductase inhibitor administered every other day for 12 weeks.	Drug: Tamsulosin; Tamsulosin hydrochloride 0.4 mg administered orally either once daily or every other day according to the randomized treatment allocation for 12 weeks.; Drug: 5-Alpha Reductase Inhibitor; A 5-alpha reductase inhibitor (finasteride 5 mg or dutasteride 0.5 mg according to routine clinical practice) administered either once daily or every other day according to the randomized treatment allocation for 12 weeks.
Experimental: Tadalafil daily + 5ARI daily; Participants received tadalafil 5 mg once daily in combination with a 5-alpha reductase inhibitor administered once daily for 12 weeks.	Drug: 5-Alpha Reductase Inhibitor; A 5-alpha reductase inhibitor (finasteride 5 mg or dutasteride 0.5 mg according to routine clinical practice) administered either once daily or every other day according to the randomized treatment allocation for 12 weeks.; Drug: Tadalafil; Tadalafil 5 mg administered orally either once daily or every other day according to the randomized treatment allocation for 12 weeks.
Experimental: Tadalafil daily + 5ARI every other day; Participants received tadalafil 5 mg once daily combined with a 5-alpha reductase inhibitor administered every other day for 12 weeks.	Drug: 5-Alpha Reductase Inhibitor; A 5-alpha reductase inhibitor (finasteride 5 mg or dutasteride 0.5 mg according to routine clinical practice) administered either once daily or every other day according to the randomized treatment allocation for 12 weeks.; Drug: Tadalafil; Tadalafil 5 mg administered orally either once daily or every other day according to the randomized treatment allocation for 12 weeks.
Experimental: Tadalafil every other day + 5ARI every other day; Participants received tadalafil 5 mg every other day combined with a 5-alpha reductase inhibitor administered every other day for 12 weeks.	Drug: 5-Alpha Reductase Inhibitor; A 5-alpha reductase inhibitor (finasteride 5 mg or dutasteride 0.5 mg according to routine clinical practice) administered either once daily or every other day according to the randomized treatment allocation for 12 weeks.; Drug: Tadalafil; Tadalafil 5 mg administered orally either once daily or every other day according to the randomized treatment allocation for 12 weeks.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Lower Urinary Tract Symptoms (IPSS)	Change in the International Prostate Symptom Score (IPSS) from baseline to Week 12. Higher scores indicate more severe symptoms; a reduction in score reflects clinical improvement.	Baseline and Week 12

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Erectile Function	Change in the International Index of Erectile Function-Erectile Function domain (IIEF-EF) score from baseline to Week 12. Higher scores indicate better erectile function.	Baseline and Week 12
Change in Ejaculatory Function	Change in the Male Sexual Health Questionnaire-Ejaculatory Dysfunction (MSHQ-EjD) score from baseline to Week 12.	Baseline and Week 12
Change in Maximum Urinary Flow Rate (Qmax)	Change in maximum urinary flow rate measured by uroflowmetry from baseline to Week 12.	Baseline and Week 12
Change in Prostate Volume	Change in prostate volume measured by transrectal ultrasonography (TRUS) from baseline to Week 12.	Baseline and Week 12
Change in Prostate-Specific Antigen (PSA)	Change in serum prostate-specific antigen (PSA) level from baseline to Week 12.	Baseline and Week 12
Change in Post-Void Residual Volume (PVR)	Change in post-void residual urine volume measured by bladder ultrasound from baseline to Week 12.	Baseline and Week 12
Incidence of Treatment-Related Adverse Events	Frequency and type of treatment-emergent adverse events, including dizziness, orthostatic hypotension, headache, flushing, dyspepsia, gynecomastia, decreased libido, erectile dysfunction, and ejaculatory dysfunction.	Throughout the 12-week treatment period

Collaborators and Investigators

• Sponsor: Beni-Suef University
• Investigators: Principal Investigator: Omar S Taha, MBBCh, Department of Urology, Faculty of Medicine, Beni-Suef University

Publications and helpful links

General Publications

• Gacci M, Ficarra V, Sebastianelli A, Corona G, Serni S, Shariat SF, Maggi M, Zattoni F, Carini M, Novara G. Impact of medical treatments for male lower urinary tract symptoms due to benign prostatic hyperplasia on ejaculatory function: a systematic review and meta-analysis. J Sex Med. 2014 Jun;11(6):1554-66. doi: 10.1111/jsm.12525. Epub 2014 Apr 7.
• Lepor H. Alpha blockers for the treatment of benign prostatic hyperplasia. Rev Urol. 2007 Fall;9(4):181-90.
• Giuliano F, Uckert S, Maggi M, Birder L, Kissel J, Viktrup L. The mechanism of action of phosphodiesterase type 5 inhibitors in the treatment of lower urinary tract symptoms related to benign prostatic hyperplasia. Eur Urol. 2013 Mar;63(3):506-16. doi: 10.1016/j.eururo.2012.09.006. Epub 2012 Sep 11.

Study record dates

Study Major Dates

• Primary Completion (Actual): January 1, 2026
• Study Completion (Actual): January 1, 2026

Study Registration Dates

• First Submitted: July 15, 2026
• First Submitted That Met QC Criteria: July 15, 2026
• First Posted (Actual): July 20, 2026

Study Record Updates

• Last Update Posted (Actual): July 20, 2026
• Last Update Submitted That Met QC Criteria: July 15, 2026
• Last Verified: July 1, 2026

More Information

Terms related to this study

• Keywords: IPSS; Benign Prostatic Hyperplasia; Randomized Controlled Trial; Lower Urinary Tract Symptoms; LUTS; Dutasteride; Tadalafil; BPH; Tamsulosin; Urology; Finasteride; Erectile Function; Ejaculatory Dysfunction; PDE5 Inhibitors; 5-Alpha Reductase Inhibitors; 5ARI; Phosphodiesterase-5 Inhibitors
• Additional Relevant MeSH Terms: Urogenital Diseases; Genital Diseases; Mental Disorders; Genital Diseases, Male; Prostatic Diseases; Male Urogenital Diseases; Urological Manifestations; Sexual Dysfunction, Physiological; Sexual Dysfunctions, Psychological; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Ejaculatory Dysfunction; Prostatic Hyperplasia; Erectile Dysfunction; Lower Urinary Tract Symptoms; Physiological Effects of Drugs; Molecular Mechanisms of Pharmacological Action; Hormones, Hormone Substitutes, and Hormone Antagonists; Enzyme Inhibitors; Steroid Synthesis Inhibitors; Hormone Antagonists; Sulfur Compounds; Organic Chemicals; Pyridines; Heterocyclic Compounds, 1-Ring; Heterocyclic Compounds; Heterocyclic Compounds, 2-Ring; Heterocyclic Compounds, Fused-Ring; Pharmacologic Actions; Chemical Actions and Uses; Hydrocarbons; Hydrocarbons, Cyclic; Hydrocarbons, Aromatic; Amides; Indoles; Benzene Derivatives; Indole Alkaloids; Benzenesulfonamides; Sulfonamides; Sulfones; Heterocyclic Compounds, 3-Ring; Carbolines; Tadalafil; Tamsulosin; 5-alpha Reductase Inhibitors
• Other Study ID Numbers: FMBSUREC/07092025/Taha

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No